The present invention relates to a two speed transmission, in particular a pre-transmission for an auxiliary aggregate in motor vehicles.
Two-speed transmissions are known in the art. One of such transmissions is disclosed for example in U.S. Pat. No. 4,854,192 and is formed as a centrifugal-force controlled two speed transmission. Such a transmission serves for example to convert an input rotary speed available from a drive machine of the motor vehicle into an output rotary speed of the transmission. The conversion is performed in dependence on the rotary speed from a rotary speed of the input shaft of the transmission. Thereby an auxiliary aggregate of the motor vehicle must receive not the total rotary speed number of the drive machine of the motor vehicle. The disadvantage of the two speed transmission disclosed in U.S. Pat. No. 4,854,192 is that it has a relatively large construction. For converting the rotary speed, means which act axially to the rotary axis of the transmission are provided, which lead to a correspondingly great mounting space. Furthermore, a plurality of components are arranged, which lead to a relatively high manufacturing cost.